33 COE borosillicate glass rod by Momka's Glass.
MB011 Cobalt Blue is easy to work with and is little stiffer than other transparent colors. Cobalt can take lots of heat. Avoid reducing flame. Neutral flame works best.
Diameter: 3/16" - 5/16" (5mm-8mm)
Length: Approximately 20" (51cm)
Sold by the rod.